options: Introduce ssh_bind_options_parse_config()

The added API allows setting the options of a given bind context through
a configuration file.  The default global configuration file
"/etc/ssh/libssh_server_config" is parsed before the provided
configuration file, if it hasn't been parsed yet.

Signed-off-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

include/libssh/bind.h

@@ -46,6 +46,7 @@ struct ssh_bind_struct {
   unsigned int bindport;
   int blocking;
   int toaccept;
+  bool config_processed;
 };
 
 struct ssh_poll_handle_struct *ssh_bind_get_poll(struct ssh_bind_struct

include/libssh/server.h

@@ -90,6 +90,9 @@ LIBSSH_API ssh_bind ssh_bind_new(void);
 LIBSSH_API int ssh_bind_options_set(ssh_bind sshbind,
     enum ssh_bind_options_e type, const void *value);
 
+LIBSSH_API int ssh_bind_options_parse_config(ssh_bind sshbind,
+    const char *filename);
+
 /**
  * @brief Start listening to the socket.
  *

src/options.c

@@ -39,6 +39,7 @@
 #ifdef WITH_SERVER
 #include "libssh/server.h"
 #include "libssh/bind.h"
+#include "libssh/bind_config.h"
 #endif
 
 /**
@@ -1894,6 +1895,49 @@ int ssh_bind_options_set(ssh_bind sshbind, enum ssh_bind_options_e type,
 
   return 0;
 }
+
+/**
+ * @brief Parse a ssh bind options configuration file.
+ *
+ * This parses the options file and set them to the ssh_bind handle provided. If
+ * an option was previously set, it is overridden. If the global configuration
+ * hasn't been processed yet, it is processed prior to the provided file.
+ *
+ * @param  sshbind      SSH bind handle
+ *
+ * @param  filename     The options file to use; if NULL only the global
+ *                      configuration is parsed and applied (if it haven't been
+ *                      processed before).
+ *
+ * @return 0 on success, < 0 on error.
+ */
+int ssh_bind_options_parse_config(ssh_bind sshbind, const char *filename)
+{
+    int rc = 0;
+
+    if (sshbind == NULL) {
+        return -1;
+    }
+
+    /* If the global default configuration hasn't been processed yet, process it
+     * before the provided configuration. */
+    if (!(sshbind->config_processed)) {
+        rc = ssh_bind_config_parse_file(sshbind,
+                                        "/etc/ssh/libssh_server_config");
+        if (rc != 0) {
+            return rc;
+        }
+        sshbind->config_processed = true;
+    }
+
+    if (filename != NULL) {
+        /* Apply the user provided configuration */
+        rc = ssh_bind_config_parse_file(sshbind, filename);
+    }
+
+    return rc;
+}
+
 #endif
 
 /** @} */

tests/unittests/torture_options.c

@@ -15,6 +15,7 @@
 #include <libssh/options.h>
 #ifdef WITH_SERVER
 #include <libssh/bind.h>
+#define LIBSSH_CUSTOM_BIND_CONFIG_FILE "my_bind_config"
 #endif
 #ifdef HAVE_DSA
 #define LIBSSH_DSA_TESTKEY        "libssh_testkey.id_dsa"
@@ -751,7 +752,7 @@ struct bind_st {
     ssh_bind bind;
 };
 
-static int setup_key_files(void **state)
+static int ssh_bind_setup_files(void **state)
 {
     struct bind_st *test_state = NULL;
     char *cwd = NULL;
@@ -792,6 +793,8 @@ static int setup_key_files(void **state)
     torture_write_file(LIBSSH_DSA_TESTKEY,
                        torture_get_openssh_testkey(SSH_KEYTYPE_DSS, 0, 0));
 #endif
+    torture_write_file(LIBSSH_CUSTOM_BIND_CONFIG_FILE,
+                       "Port 42\n");
     return 0;
 }
 
@@ -802,7 +805,7 @@ static int sshbind_setup(void **state)
     int rc;
     struct bind_st *test_state = NULL;
 
-    rc = setup_key_files((void **)&test_state);
+    rc = ssh_bind_setup_files((void **)&test_state);
     assert_int_equal(rc, 0);
     assert_non_null(test_state);
 
@@ -1294,6 +1297,23 @@ static void torture_bind_options_set_macs(void **state)
     assert_int_not_equal(rc, 0);
 }
 
+static void torture_bind_options_parse_config(void **state)
+{
+    struct bind_st *test_state;
+    ssh_bind bind;
+    int rc;
+
+    assert_non_null(state);
+    test_state = *((struct bind_st **)state);
+    assert_non_null(test_state);
+    assert_non_null(test_state->bind);
+    bind = test_state->bind;
+
+    rc = ssh_bind_options_parse_config(bind, LIBSSH_CUSTOM_BIND_CONFIG_FILE);
+    assert_int_equal(rc, 0);
+    assert_int_equal(bind->bindport, 42);
+}
+
 #endif /* WITH_SERVER */
 
 
@@ -1359,6 +1379,8 @@ int torture_run_tests(void) {
                 sshbind_setup, sshbind_teardown),
         cmocka_unit_test_setup_teardown(torture_bind_options_set_macs,
                 sshbind_setup, sshbind_teardown),
+        cmocka_unit_test_setup_teardown(torture_bind_options_parse_config,
+                sshbind_setup, sshbind_teardown),
     };
 #endif /* WITH_SERVER */